Society would benefit from a better understanding of the complicated processes that affect health over the life span. Particularly useful would be a better understanding of the role of key factors that can be influenced by public and private policy. We will focus on work-life and health habits as key determinants of health and examine how they interact with health over the life course. Early choices with regard to work-life (e.g. occupation) and health habits (initiation of smoking, drinking, and obesity) can have durable effects and thus can affect later health. The overallaim of this proposal is to examine the dynamic interplay over the life cycle among work-life, health habits, and health outcomes. Wewill build a life cycle model using several longitudinal datasets covering the age range from adolescence to late life. Our model aims to assess associations and potential multidirectional causality among these factors. We will accomplish our goals by bridging methodologies across disciplines to best address our research questions. Specific Aim 1: Analyze labor market experiences and health habits as determinants of health in old age, and investigate whether these are better characterized by static measures or dynamic processes. Specific Aim 2: Model the interplay among the principalrisk factors derived from Aim 1, recognizing and modeling which factors are pre-determined and which are causal at different points in the life cycle. Allow for multi-directionality among labor market variables, health habits, and health outcomes, and changes in these relationships with age. Specific Aim 3: Determine whether there are differences in the relationships identified in Aims 1 and 2 across health measures and race and gender sub-populations. Usemultiple datasets to assessthe robustness of findings. Specific Aim 4: Based on our findings, identify key public and private policies that could, especially early in life, have important impacts on the trajectory of health leading to a long and high functioning life. Disseminate findings to academic audiences andtranslate findings to be more accessible to broader audiences who could benefit from the knowledge. The primary datasets that will be used are: the Panel Study of Income Dynamics (PSID) and the Health and Retirement Study (MRS). We will also use the National Longitudinal Study of Youth (NLSY) and the Study of Assets and Health Dynamics among the Oldest Old (AHEAD) to focus on younger and older individuals, respectively. Together these longitudinal datasets cover the life span and each contains measures of health, health habits and labor market characteristics.